title: Subunits of the histone chaperone CAF1 also mediate assembly of protamine-based chromatin.
abstract: One of the most dramatic forms of chromatin reorganization occurs during spermatogenesis, when the paternal genome is repackaged from a nucleosomal to a protamine-based structure. We assessed the role of the canonical histone chaperone CAF1 in Drosophila spermatogenesis. In this process, CAF1 does not behave as a complex, but its subunits display distinct chromatin dynamics. During histone-to-protamine replacement, CAF1-p180 dissociates from the DNA while CAF1-p75 binds and stays on as a component of sperm chromatin. Association of CAF1-p75 with the paternal genome depends on CAF1-p180 and protamines. Conversely, CAF1-p75 binds protamines and is required for their incorporation into sperm chromatin. Histone removal, however, occurs independently of CAF1 or protamines. Thus, CAF1-p180 and CAF1-p75 function in a temporal hierarchy during sperm chromatin assembly, with CAF1-p75 acting as a protamine-loading factor. These results show that CAF1 subunits mediate the assembly of two fundamentally different forms of chromatin.
authors.affiliation: Department of Biochemistry, Erasmus University Medical Centre, P.O. Box 1738, 3000 DR, Rotterdam, The Netherlands.
authors.forename: Cécile M
authors.initials: CM
authors.lastname: Doyen
authors.forename: Yuri M
authors.initials: YM
authors.lastname: Moshkin
authors.forename: Gillian E
authors.initials: GE
authors.lastname: Chalkley
authors.forename: Karel
authors.initials: K
authors.lastname: Bezstarosti
authors.forename: Jeroen A A
authors.initials: JA
authors.lastname: Demmers
authors.forename: Christina
authors.initials: C
authors.lastname: Rathke
authors.forename: Renate
authors.initials: R
authors.lastname: Renkawitz-Pohl
authors.forename: C Peter
authors.initials: CP
authors.lastname: Verrijzer
mesh_terms: D000818:Animals; D002843:Chromatin / Q000378:metabolism*; D042002:Chromatin Assembly and Disassembly; D004330:Drosophila / Q000235:genetics / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D008297:Male; D011479:Protamines / Q000378:metabolism*; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D056505:Retinoblastoma-Binding Protein 4 / Q000235:genetics / Q000378:metabolism*; D013094:Spermatozoa / Q000378:metabolism
chemical_list: C110251:Caf1-55 protein, Drosophila; D002843:Chromatin; D029721:Drosophila Proteins; D006657:Histones; D011479:Protamines; D021122:Protein Subunits; D056505:Retinoblastoma-Binding Protein 4